Mererid is the Welsh word for "pearl" — derived from the Greek margaritēs, the same root as Margaret. Used in Welsh-speaking communities.
Mererid Hopwood (born 1964) is the Welsh poet and the first woman to win the Chair at the National Eisteddfod of Wales (2001).
Mererid does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
In Pythagorean numerology the letters of Mererid reduce to 9, The Giver. This is a traditional interpretive system, not a factual claim about the name.